sym·​bi·​ont | \ ˈsim-bē-ˌänt How to pronounce symbiont (audio) \

Definition of symbiont

: an organism living in symbiosis especially : the smaller member of a symbiotic pair

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Examples of symbiont in a Sentence

Recent Examples on the Web Certain algae species serve as symbionts for Cassiopea jellyfish, providing the animals with nutrients harvested from sunlight by way of photosynthesis. Cheryl Ames, National Geographic, "THE BEST OF NATIONAL GEOGRAPHIC DELIVERED TO YOUR INBOX," 13 Feb. 2020 In other sap-sucking insects, symbionts serve additional functions, Moran and her colleagues discovered. Elizabeth Pennisi, Science | AAAS, "A love of insects and their microbial partners helped this biologist reveal secrets of symbiosis," 14 Nov. 2019 Skillings and other critics argue that there just isn’t enough evidence of vertical transmission of symbionts to allow for the holobiont to be a coherent evolutionary individual. Quanta Magazine, "Should Evolution Treat Our Microbes as Part of Us?," 20 Nov. 2018 This jet forces out oxygen that accumulates in the middle of the polyp (thanks to its resident symbionts, photosynthetic algae called zooxanthellae). Scientific American, "Nanomachines, Jellyfish Hugs and Hurricane Dorian From Space: The Week's Best Science GIFs," 30 Aug. 2019 For decades, researchers have known that mitochondria are derived from bacteria that became internal symbionts of archaeal cells, but details of how that happened have been sketchy. Quanta Magazine, "Researchers Rethink the Ancestry of Complex Cells," 9 Apr. 2019 Filaments of the protein actin, for example, could have stabilized contacts between the hosts and symbionts and improved the coupling of their metabolisms. Quanta Magazine, "Researchers Rethink the Ancestry of Complex Cells," 9 Apr. 2019 In other words, can humans cultivate a better terrain for their symbionts? Jason Pontin, WIRED, "The 19th-Century Crank Who Tried to Tell Us About the Microbiome," 15 June 2018 When stressed by heat these symbionts start producing dangerous oxidants. The Economist, "Mass die-offs are driving efforts to create hardier corals," 15 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'symbiont.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of symbiont

1887, in the meaning defined above

History and Etymology for symbiont

borrowed from German Symbiont, probably altered (after Greek ont-, stem of ṓn, present participle of eînai "to be") from symbiount-, stem of symbiôn, present participle of symbioûn "to live together" — more at symbiosis

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Time Traveler for symbiont

Time Traveler

The first known use of symbiont was in 1887

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Cite this Entry

“Symbiont.” Dictionary, Merriam-Webster, Accessed 31 May. 2020.

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More Definitions for symbiont


sym·​bi·​ont | \ ˈsim-ˌbī-ˌänt How to pronounce symbiont (audio) , -bē- How to pronounce symbiont (audio) \

Medical Definition of symbiont

: an organism living in symbiosis especially : the smaller member of a symbiotic pair

called also symbiote

Other Words from symbiont

symbiontic \ ˌsim-​ˌbī-​ˈänt-​ik, -​bē-​ How to pronounce symbiontic (audio) \ adjective

More from Merriam-Webster on symbiont

Rhyming Dictionary: Words that rhyme with symbiont Encyclopedia article about symbiont

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